' When the user uses the facebook login page, the redirect back here will will have the auth_token in the query params
Dim authToken As String = Request.QueryString("auth_token")

If Not [String].IsNullOrEmpty(sessionKey) Then
' We have already established a session on behalf of this user
fbService.SessionKey = sessionKey
fbService.uid = userId
ElseIf Not [String].IsNullOrEmpty(authToken) Then
' This will be executed when facebook login redirects to our page
fbService.CreateSession(authToken)
Session("facebook_session_key") = fbService.SessionKey
Session("facebook_userId") = fbService.uid
Session("facebook_session_expires") = fbService.SessionExpires
Else
' Need to login
Response.Redirect("http://www.facebook.com/login.php?api_key=" + fbService.ApplicationKey + "&v=1.0")
End If

If Not IsPostBack Then
RefreshFBML()
End If
End Sub
Private Sub RefreshFBML()
Response.Write("Testing the apps dude.....")
fbService.profile.setFBML(fbService.uid, "I am testing the apps...", "I am testing the apps...", "")
End Sub
End Class

Hi guys,
I have encountered this problem myself while using the Binaries Facebook .Net toolkit and after some drilling i found that a specific version of Facebook.dll assembly is Mal-functioning.
you can see the difference at
this page.... , it demonstrate the difference between the two Facebook.dll assemblies and specify which one is working and which one does not.
Make a long story short :) do not use the 2.0.3142.23334 version of Facebook.dll assembly.